You are not charged for Azure Active Directory Groups. Therefore, deleting unused groups will not reduce your Azure costs.
References:
https://docs.microsoft.com/en-us/azure/advisor/advisor-cost-recommendations#reduce-costs-by-deleting-or-reconfiguring-idle-virtual-network-gateways

Azure Site Recovery helps ensure business continuity by keeping business apps and workloads running during outages. Site Recovery replicates workloads running on physical and virtual machines (VMs) from a primary site to a secondary location.
References:
https://docs.microsoft.com/en-us/azure/site-recovery/site-recovery-overview

Explanation:

Explanation:
Microsoft Trust Center
The Trust Center provides:
* In-depth information about security, privacy, compliance offerings, policies, features, and practices across Microsoft cloud products.
* Additional resources for each topic.
* Links to the security, privacy, and compliance blogs and upcoming events.
https://www.azureguru.org/explore-the-microsoft-trust-center/#:~:text=The%20Trust%20Center%
20provides%3A,Additional%20resources%20for%20each%20topic.

Azure policies can be used to define requirements for resource properties during deployment and for already existing resources. Azure Policy controls properties such as the types or locations of resources.
Azure Policy is a service in Azure that you use to create, assign, and manage policies. These policies enforce different rules and effects over your resources, so those resources stay compliant with your corporate standards and service level agreements. Azure Policy meets this need by evaluating your resources for non-compliance with assigned policies. All data stored by Azure Policy is encrypted at rest.
Azure Policy offers several built-in policies that are available by default. In this question, we would use the
'Allowed Locations' policy to define the locations where resources can be deployed.
References:
https://docs.microsoft.com/en-us/azure/governance/policy/overview